XVI 



BOTANY. 



is supported, the petiole; 3. Two little appendages or lobes at or 

 near the base of the petiole, the stipules. (Fig. IX.) 



Fig. IX. 



Fio. X. 



Fig. IX.— Diagram showing parts of leaf. 



Fig. X.— Diagram of lobed leaf (piunately lobed) showing lobes and sinuses. 



Blade. — The blade is always one piece when the leaf is very 

 young (i.e., very early in its growth in the bud). In many cases 

 it remains so in all its subsequent growth, and is said to be sim- 

 ple. Very commonly, however, even in simple leaves the blade has 

 branched more or less in its growth, giv- 

 ing rise to lobes of various sizes and forms 

 (the hied leaf). The indentation between 

 two lobes is termed a sinus (Fig. X). 

 When the branching is so profound that 

 ' the lobes have become separable leaflets, 

 the blade is said to be compound. 



The branches of the blade may radiate 

 from a common central point (radiately 

 lobed, radiately compound, or, more com- 

 FiQ. XI.— Eadiately or monly, pakruttely lobed. Fig. XI, palmately 

 palmately lobed leaf . compound, Fig. XII); or they may grow 



out on opposite sides of an axial portion {pinnately lobed. Fig. X, 



